Perhaps you should try some spelling variations:
ve triet » va trien, su triet
thu nang » thi nang, thu hang, tho nang
thu bang » thu ban, thu hang, chu bang
cao duc » dao duc, cao suc, giao duc
su sach » so sach, vu sach
hieu va » lieu va, hieu qua
ma hoi » mai hoi, xa hoi, ma hoa
va cao » va cac, va co, va dao
va can » va chan, va cac, va ban
va con » va cong, va co
ban ve » ban va

You may be able to get more results by adjusting your search query.

• Performing a fuzzy search may retrieve terms with similar spellings: su sach ((thu nang) or (thu bang)) ma hoi. hieu va cao duc ((va can) OR (va con)) ban ve triet~.
• If you are trying to use Boolean operators, they must be ALL CAPS: su sach ((thu nang) OR (thu bang)) ma hoi. hieu va cao duc ((va can) OR (va con)) ban ve triet.
• The words AND, OR and NOT may confuse the search; try adding quotes: "su sach ((thu nang) or (thu bang)) ma hoi. hieu va cao duc ((va can) OR (va con)) ban ve triet".
• Adding a wildcard symbol may retrieve word variants: su sach ((thu nang) or (thu bang)) ma hoi. hieu va cao duc ((va can) OR (va con)) ban ve triet*.